Interactivity and animation (hereafter “motion”) are important aspects of modern software, but have no clear place in classical software design architectures. This leads to complex implementations that are neither modular nor extensible. Motion is typically an afterthought of the software engineering process and engineering teams pay the cost of this afterthought in maintenance and lack of portability. Core Animation is one animation technology which powers most of the iOS operating system. This technology includes a render server (a separate process) and a set of animation types including “basic” animations from one value to another, “keyframe” animations over an array of key frames, and “emitters” which generate views that follow a particle effect. Web animation is another animation technology which powers HTML animations and is a Javascript standard defined by the W3C.